1. Field of the Invention
This invention relates to synthetic papers and more particularly to synthetic papers on which letters, pictures, etc., can be printed by offset printing, photogravure printing, etc., or can be written upon with a pencil, a fountain pen, etc., and which have excellent luster and sliding properties.
Such synthetic paper can be utilized as highclass makeup paper, art paper, paper patterns for dresses, paper for a poster, and so forth. Moreover, it can be used as a large-sized stretch wrapping film for which sliding properties are required, a substrate on which a sticker or an adhesive label is provided and for which stripping properties are required, and a white board on which letters, etc., can be written with chalk, marking pen using peelable ink, aqueous ink pen or oily ink pen.
2. Description of the Prior Art
As is known in the art, a composition comprising a film-forming thermoplastic resin, an inorganic filler, e.g., talc, clay, diatomaceous earth, titanium oxide, etc., a thermosetting resin powder or a thermoplastic resin which is not compatible with a film-forming thermoplastic resin can be processed to form a sheet (also referred to as a film), and the sheet thus-formed is stretched at a temperature lower than the melting temperature of the matrix resin of the film or sheet monoaxially or in a plurality of directions, to thereby produce a film or synthetic paper having a matt-finished surface on which letters, etc., can be written by a writing means or by printing. See, for example, U.S. Pat. Nos. 3,154,461, 3,515,626, and 3,814,193. See also British Pat. No. 1,096,064.
The matt-finish of the surface of the film formed by the stretching, however, suffers from the disadvantage that it results in adverse influences on sliding and stripping properties, although it improves printing and writing properties. That is, where such prior art synthetic paper is used as a large-sized stretch wrapping film which is employed, e.g., to wrap grain bags mounted on a pallette together with the pallette or as a substrate on which a sticker is provided, such matt-finish is not preferred, in view of the following considerations:
(1) Where used in large-sized stretch wrapping, it is subjected to high tension and, therefore, when the wound film is removed from a group of rolls, it produces an unpleasant sound, and also reduces workability because of the lack of the sliding properties.
(2) In order to improve the stripping properties, it is necessary to coat wax or a silicon resin on the matt-finished surface.